Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=8.

A321064

Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=8.

Terms

    a(0) =654424a(1) =19209584a(2) =769534688a(3) =39729927744

External references